Randomness in size and granularity greatly reduces its usefulness. I didn't find any that were too gross, but there were some that were so good I would never use them. Maybe it's better to buy exactly what you need. I make wooden toys and use them to sand small parts. Especially in holes.
Merit M 9 2 5 Extra Shank Length Cartridge Diameter
3 Review
Effortless Sanding with Dremel EZ407SA Drum Sanding Mandrel
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π§ Astro Tools 1442 A34 10 24 Mandrel: Top-Quality Precision Tool for Efficient Operations
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π¨ Enhance Your Woodworking Skills with PSI Woodworking PKM FLC Maxi Mandrel Morse
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